TY - JOUR
T1 - Prolonged, Brain-wide expression of nuclear-localized GCaMP3 for functional circuit mapping
AU - Kim, Christina K.
AU - Miri, Andrew
AU - Leung, Louis C.
AU - Berndt, Andre
AU - Mourrain, Philippe
AU - Tank, David W.
AU - Burdine, Rebecca D.
N1 - Publisher Copyright:
© 2014 Kim, Miri, Leung, Berndt, Mourrain, Tank and Burdine.
Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2014/11/26
Y1 - 2014/11/26
N2 - Larval zebrafish offer the potential for large-scale optical imaging of neural activity throughout the central nervous system; however, several barriers challenge their utility. First, ∼panneuronal probe expression has to date only been demonstrated at early larval stages up to 7 days post-fertilization (dpf), precluding imaging at later time points when circuits are more mature. Second, nuclear exclusion of genetically-encoded calcium indicators (GECIs) limits the resolution of functional fluorescence signals collected during imaging. Here, we report the creation of transgenic zebrafish strains exhibiting robust, nuclearly targeted expression of GCaMP3 across the brain up to at least 14 dpf utilizing a previously described optimized Gal4-UAS system. We confirmed both nuclear targeting and functionality of the modified probe in vitro and measured its kinetics in response to action potentials (APs). We then demonstrated in vivo functionality of nuclear-localized GCaMP3 in transgenic zebrafish strains by identifying eye position-sensitive fluorescence fluctuations in caudal hindbrain neurons during spontaneous eye movements. Our methodological approach will facilitate studies of larval zebrafish circuitry by both improving resolution of functional Ca2+ signals and by allowing brain-wide expression of improved GECIs, or potentially any probe, further into development.
AB - Larval zebrafish offer the potential for large-scale optical imaging of neural activity throughout the central nervous system; however, several barriers challenge their utility. First, ∼panneuronal probe expression has to date only been demonstrated at early larval stages up to 7 days post-fertilization (dpf), precluding imaging at later time points when circuits are more mature. Second, nuclear exclusion of genetically-encoded calcium indicators (GECIs) limits the resolution of functional fluorescence signals collected during imaging. Here, we report the creation of transgenic zebrafish strains exhibiting robust, nuclearly targeted expression of GCaMP3 across the brain up to at least 14 dpf utilizing a previously described optimized Gal4-UAS system. We confirmed both nuclear targeting and functionality of the modified probe in vitro and measured its kinetics in response to action potentials (APs). We then demonstrated in vivo functionality of nuclear-localized GCaMP3 in transgenic zebrafish strains by identifying eye position-sensitive fluorescence fluctuations in caudal hindbrain neurons during spontaneous eye movements. Our methodological approach will facilitate studies of larval zebrafish circuitry by both improving resolution of functional Ca2+ signals and by allowing brain-wide expression of improved GECIs, or potentially any probe, further into development.
KW - Brain-wide expression
KW - Genetically encoded calcium indicators
KW - In vivo calcium imaging
KW - Nuclear calcium signals
KW - Transgenic zebrafish
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U2 - 10.3389/fncir.2014.00138
DO - 10.3389/fncir.2014.00138
M3 - Article
C2 - 25505384
AN - SCOPUS:84912533574
VL - 8
JO - Frontiers in Neural Circuits
JF - Frontiers in Neural Circuits
SN - 1662-5110
IS - NOV
M1 - 138
ER -